Re: (-8)^(1/3)
- To: mathgroup at smc.vnet.net
- Subject: [mg31299] Re: (-8)^(1/3)
- From: "Steve Luttrell" <luttrell at signal.qinetiq.com>
- Date: Sat, 27 Oct 2001 01:08:08 -0400 (EDT)
- Organization: Defence Evaluation & Research Agency
- References: <9rb6rm$5ch$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
"LuisMa" <nospam at newsranger.com> wrote in message news:9rb6rm$5ch$1 at smc.vnet.net... > When I enter > (-8)^(1/3) > Mathematica answer > 1 + 1.73205i, > but I need > (-8)^(1/3) = -2 > How can I get it? If you evaluate this: Solve[x^3 == -8, x] then you get the following output: {{x -> -2}, {x -> 2*(-1)^(1/3)}, {x -> -2*(-1)^(2/3)}} You can then use this to replace x by whichever of the 3 roots that you require. -- Steve Luttrell QinetiQ Malvern Technology Centre UK